With the number of terrestrial sources that yield novel treatments for human disease decreasing year by year, the oceans have been tapped as a promising resource for discovering new natural biomedicines.
Two studies by scientists at UC San Diego, each utilizing mass spectrometry in novel ways, have helped narrow the gap in identifying potent natural compounds from the sea that could one day treat diseases such as cancer. The research, published in the journals Proceedings of the National Academy of Sciences (PNAS) and Molecular Biosystems, was led by research groups headed by William Gerwick of the Center for Marine Biotechnology and Biomedicine at Scripps Institution of Oceanography at UC San Diego and the UCSD Skaggs School of Pharmacy and Pharmaceutical Sciences, and Pieter Dorrestein of the UCSD Skaggs School.
Because the ocean environment offers a wealth of new sources for future therapeutic products, marine biologists and chemists have been seeking ways to identify the specific processes that produce such compounds within sponges, mollusks and other marine invertebrates. In the March issue of the journal Molecular Biosystems, the scientists describe success in using new technology called natural product MALDI-TOF (Matrix Assisted Laser Desorption Ionization-Time of Flight) imaging mass spectrometry, an imaging technique that can uniquely probe the inner workings of marine organisms.
In the case of marine sponges, researchers often have trouble deciphering whether the therapeutic compounds they produce are being manufactured by the sponge, bacteria within the sponge, or a combination of the two in a symbiotic relationship. In the PNAS paper, published in February, researchers T. Luke Simmons, Gerwick, Dorrestein and their colleagues probe such production issues, or “biosynthetic origins,” and review a variety of traditional and emerging techniques being used to localize the molecular machinery responsible for potential new drug products.
“Sea hares, for example, eat cyanobacteria (blue-green algae) and we know for a fact that they assimilate their chemistry,” said Gerwick. “With sponges, there are communities of organisms living within them. What we need to find out is: within those communities, who really possesses the genes to make the critical compounds"”